The key is in NATO Phonetic Alphabet

Tango Hotel Echo Kilo Echo Yankee India Sierra

Letter Breakdown

LetterNATO Word
TTango
HHotel
EEcho
KKilo
EEcho
YYankee
IIndia
SSierra

Full NATO Phonetic Alphabet

A
Alpha
B
Bravo
C
Charlie
D
Delta
E
Echo
F
Foxtrot
G
Golf
H
Hotel
I
India
J
Juliet
K
Kilo
L
Lima
M
Mike
N
November
O
Oscar
P
Papa
Q
Quebec
R
Romeo
S
Sierra
T
Tango
U
Uniform
V
Victor
W
Whiskey
X
X-ray
Y
Yankee
Z
Zulu